Parallel-crank motion for radial engines



Oct. 20, 1925.

c. l. PRESTON PARALLEL CRANK MOTION FOR RADIAL ENGINES 3 Sheets-Sheet 1 Filed Dec. 14 1922 m 3mm Stream Oct 20,1925.

0. PRESTON YARALLJLL CRANK MOTION FOR RADIAL ENGINES Filed Dec. 14. 1922 s sheets-she d 2 T7706 YTZOZ Oct. 20, 1925..

1,557,875 c. I. PRESTON PARALLEL CRANK MOTION FOR RADIAL ENGINES Filed Dec. 14, 1922 3 Sheets-Sheet 5 3 vwe n4 01- To all whom it may concern:

mamaoa an,

, 15 1x 2 PATENT OFFICE,

' 'mi rnnsron, or Damon-r, IOWA:

rananmmx norms For. nanru.

Application fledDeember. 14, 1922. Serial no. seam Be it known that I, Cnanmss I. Plms'ron,

a-citizen of the United States, residing at Davenport, in the county of Scott and State of Iowa, have invented'certain new and useful Improvements in Parallel-Crank Motions for Radial Engines, of which the following is a specification.

This invention relates to a parallel crank motion for radial engines, the object in view being to produceaparallel crank radial engine, preferably of the air-cooled type, having certain distinctive and novel features designed to give greater compactness qualities at high'speeds, and greater relia ility in use.

smoother The parallel crank motion herein desci'ibed and shown, is designed to produce a more perfect balance than has hithertof bee n at-o tained by radial engines, having'a rotary shaft and non-rotary or stationary cylinders arranged radial relation thereto, thus rendering possible higher speed and uently more power for a given size or cylin er.

'Under connecting rods are all attached b knuckle pins to a knuckle pin yokewhic may be of annular formation or of any other preferred design, such as a disk or ring, said yoke being mounted on the crank pins of several cranks whose throws are always equal and parallel. As the cranks revolve enable one or more cannons or machine guns the yoke moves bodily in an annular path,

every int of the okegmoving in acircle the ra 'us of whi is ual to the radius or throw of the cranks. ach of the knuckle .pins describes a complete circle of the crank radius and hence all of thepistons move alike, the result being -a umform motion which maybe more clomlycounterbalanced than the master rod type of-ene, at the same timesecur' a more even ring pressure which is e ectively dis tributed. w The ropeller shaft is driven off oneor more -,0 the three cranks-above mentioned, either directly or through rs. In the smaller sizes, propeller gearing is used so that the engine may run at higher speed and thus develop its power with small cylinders, light weight, small over-all diameter and minimum head resistance.

' A further object in view is to rovide a construction of radial engine w 'ch will line as'Figure 1' passing through the contemplated construction, the.

cylinder heads.

is be inserted therethfough thus eliminatsynchronizing fully described, illustrated an claimed.

the-accompanying r 1 is a view partly in e ev tion and partly in section through the-improved radial engine taken at a right angle to the centrally located propeller shaft; I

Figure 2 is a section taken at a right angleto Figure 1 on the line 2--2 of Figure 1; Figure 3 is a partial section on the same showing mother form of knuckle yoke;

Figure 4=1s a sectiontaken on the same hne as Flg'ure 2, and on the line 4-4 of. Figure 3 sho .a tllgbularengine shaft e yo 0; v F1gure'5 1s a fragmenta section illustrating a direct drive rathei than adriveasillustratedinFigure 2.

Referrin to the drawings, the engine illustrated t erein is shown as composed of a circular series of non-rotary or stationarycylinders 5, each containing a red rocatory piston 6. -The cylinders 5 are 0 a the'aircooled t shown as provided with bustidn chambers and also encircling the The cylinders 5, are arranged around a centrally located ropeller shaft or hub 8, The connecting 9 of all of the pistons 6- are attached by annular pins '10 at their innor ends to a common knuckle in yoke "112 The yoke 11 may beef any pre erred ded'gn or formation, such as a triangle, as illustrated in F' 1, or an annular-ring as shown in 3. Under the am ment shownin igures land 2,-the knuc e pins'loof certain connecting nected to the'angles of'the triangular yoke while the ber 11 and the bearing members 12. All

11 gine so that all of the crank throws are alike I of the knuckle pins 10 are inranged in a circle. equidistant from the center of the enand each piston has an equal movement.

between theblad'es or '1 '7 which extendaround the com,

I rodsareconoonnectmgj'ods are remaimng connected by knuckle pins tobearing' mem- In a nine cylinder engine such'as is illustrated in Figure. 1, I employ three cranklike members 13 each of which is connected by a pivot 14: to the yoke 11 at one end,

said crank-like member 13 carrying a counterbalance weight 15 at the other end. lifidway between its ends each crank-like member is mounted to turn on a journal or stud shaft 16, journaled in hearings in webs or frame members 17 and 18 contained within the crank case orhousing 19 of the engine, which crank case has the cylinders 5 fas tened thereto in an suitable-way.

transmitted to the propeller shaft or theen As shown in Figure 2, the journal or' shaft of one of the crank-like members 13 has fastened thereon a gear wheel 20 which meshes, with and drives a similar gear wheel 21 fast on the propeller shaft 8, whichmay be the engine aft, as illustrated in Figure 4, and thus the powertransmittedlby the yoke 11 to the crank-like members 13- is gine shaft, as the case may be, it beingun} 13 may be .derstood that the yoke is driven in an an .nular p, path by the connecting rods9. It-

will, therefore, be understood that, in the same manner, all of the crank-like members geared to the shaft 8 andthat a es 7 number of crank-like mem gzeater or I rs 13 may be employed in accordance with th e general design-and size of the.en-

.gine' and the number of -cylinders incorporated therein. The shaft 8 is 'jdurnaled in f separate copending appilicatidn.

bearings supported by anend wall of the.

crank case 19 and one of the internal fixed webs or bearing members 17 and 18. The valve operatin mechanism shownj to the right ofthe we 18in Figure 2 neednot be herein described as it is lncorpora-ted in a In Figure 4, the yo e designated 11 is 3 fshownof. annular. or ring-like formation U theknuckle pins It? to which the knucklepins 10. bein circle so that each wi attached, all of the arranged in a true travel in a circular path, the result being exactly the" same as connecting rods 9' are that described in connection with the yoke shown in Figure 1. Figure 4, which is a tirely therethrough from end ,to end section taken at aright' an le to Figure 3,

lustrates the use of two counterbalanced ,rect said yoke in an annular more of said, crank-like: mem

'means between thepistons. and

a rotary shaft, a circular series of cylinf'the crank-like weights -15-on each crank-like 13 and Figure 4 illustrates the use 'of two counterbalanced members 15 on each cranklike member 13'. In the vdevice as illustrated in Figure 5 the shaft 16 extends outside of the casing 19 to drive the pro eller..

From the foregoing description, ta en in connection with the accompanying draws-v ings, it will be obvious that the number of crank-like members 11 may be changed to proved transmission mechanism is used,-

- and also the number of driving gear wheels or pinions used to transmit motion from the crank-like members to the propeller shaft These and man other chan es in the form,

proportion an minor details of construe tion may be resorted to without departing c from the principle of the invention.

Vhat I claim is- 1. In-a radial engine, the combinationof v a rotary shaft, a circular series of cyhnders, cooperating pistons, and ,transmlsion means between the pistons and-the engine shaft, comprising connecting rods,a knuckle pin yoke to ,which the connecting rods are attached, and crank-like members which d ipgthone or n c e a (f a driving ce'nnectlon with the'engme shaft.

2. In a radial en 'ne, .thecombination of a rotary shaft, a circular series of cylinders, cooperative pistons, and trahsmission e e g shaft, comprising. connecting I rode, a, knuckle pin yloke to. which-the connecting rods are attached, and crank-like members which direct said (yoke in an annular path, said yoke surroun in the engine shaft, one or more of'said cran -like members having driving connection with the engine shaft.

3. In a radial engine,'the combination of I dare, cooperating pistons, and 'counterbal' anced transmission means between the pis- 'tonsahd the 611%18 shaft,fcom rising connecting rods, a uckle; pin yo e to which the connecting rods are attached, and crankannular path, one or more of said cranki like members which direct said yoke in an like 'members having driving 'connection 'with the engine shaft.

'- ,4. In a radial engine, the'combination of a rotary shaft,

a suit the particular engine on which the im- 4 ad f or the engine shaft It is not necessary that i maintain it in annular. or circular. motion.

having i a circular series of cyh ders, cooperating pistons, and counterbal- I anced transmission means between the pislike members which direct said yoke in an annular ,path, said yoke surrounding the engine shaft, one or more of said crank-like members having' driving connection with the engine shaft.

5. In a radial engine, the combination of a rotary-shaft, a'circular series of cylinders cooperating pistons, and transmission means between the pistons and the engine shaft,

- comprisin connecting rods, a-knuckle pin yoke to w ich the connecting rods are attached, and crank-like members which direct said yoke in an annular path, one of said crank-like members being extended axially to form the e e shaft.

6. In a radia engine, the combination of a rotary shaft, a circular series of cylinders, cooperating pistons, and counterbalanced transmission means between the pistons and the en ine shaft, comprisin uckle pin yoke to w ich the conrods, a necting rods are attached, and crank-like members which direct said yoke in an annular path, one of said crank-like members connecting being extended axially to form the engine shaft. l 7. In a radial engine embodying a centrally arranged rotary shaft, and a circular series of cylinders disposed radially to said shaft, in combination with transmis sion means between the pistons of said cylinders and the engine shaft comprisin a knuckle pin yoke to which the connecting rods are attached, and crank-like members which direct said oke in an annular path, said yoke surrounding the engine shaft, and one or more of said crank-like members having driving connection with the engine shaft. 8. In a radial engine embodying a centrally arranged rotary shaft, and a circular series of cylinders disposed radiall to said shaft, in combination with counter alanced trans mission means between the pistons of said cylinders and the engine shaft comprising a knuckle pin yoke to which the connecting rods are'attached, and crank-like members which direct said oke in an annular path, said yoke surroun ing the engine shaft, and one or more of said crank-like members having driving connection with the engine 

